Various letters are found on some Baltimore and Kansas City trim
tags. Below are some of the letters along with the Fisher Body style
number it/they were found on as of July 19, 2014. Sometimes there is no
space between the letters and sometimes there is. Their meaning is not
documented but there are some trends that one can draw their own
conclusion from.

Baltimore:
B: B has been found on Malibu sport coupe, sport sedan, convertible, 4-door sedan,
Malibu series Custom El Camino, and L6
Greenbrier station wagon,
sometimes with D and sometimes by itself and does NOT indicate SS396 or SS454
but does not preclude the car being an SS396 or SS454 either.
D: D has been found on Malibu sport coupe, convertible, and Malibu series Custom
El Camino,
sometimes with B.
L: L has been found on Custom El Caminos.